The invention is directed to a character pattern generating apparatus and in particular to a character pattern generating apparatus suitable for use in a dot matrix printer capable of generating characters on serial printers with print heads having different print patterns.
Dot matrix type serial printers are easily adapted to print characters, figures and the like with a plurality of dot patterns. Due to the great degree of flexibility inherent in dot matrix type serial printers in expressing a wide variety of dot patterns, dot matrix type serial printers are widely used as printing output devices for word processors and computers.
In order to fully utilize the capabilities of the serial dot matrix printers, it is necessary to prepare and store pattern data which corresponds to the character patterns which are to be printed. This need to store each character as a preformed matrix of dots typically requires the character generator to have a particularly large capacity which is disadvantageous.
As the resolution of the printed dots is increased to provide sharper and clearer printing of letters and graphics displays, print heads frequently utilized print head arrangements with complimentary columns of pins P as shown in FIGS. 2A and 2B. Print heads with these staggered columns of pins produce a single column of overlapping dots D as shown in FIG. 2C by sequential printing of the columns of pins P on the same column on a paper. The pin alignment of the print head of FIG. 2A utilizes a first printing operation of the right column of pins. Next, when the print head is moved right relative to the paper or other printing medium, the left column is printed in the same column. This produces a column of overlapping dots as shown in FIG. 2C. A three column print head a shown in FIG. 2B requires three printing operations to produce the single column of overlapping dots shown in FIG. 2C. As a result of these varied print arrangements, it has been necessary to also take into consideration the pin arrangement of the printer when storing the dot pattern data. As a result, this requires considerable time in forming the pattern data. It also has the disadvantage of seriously limiting the application of a character generator to a particular print head with a particular pin arrangement. Accordingly, there is a need for a character pattern generating apparatus which can easily be utilized with different printers having different print head pin arrangements and for different font types without the need for a large capacity character generator or time consuming processing operation.